The better battery.

High -energy, rechargeable microbatteries

1

The advantages of silver-zinc batteries in portable electronics applications

The better battery.July 12, 2007

CONFIDENTIAL

Silver-Zinc Rechargeable Batteries• 50 year history in aerospace and

military• Benefits

– High energy density– Safe, water based chemistry– Mercury-free, recyclable materials

• Challenges– Zinc shape change– Separator degradation – Cost of silver

The better battery.July 12, 2007 CONFIDENTIAL

Existing Silver-Zinc Batteries

• Primary battery– 1.5V nominal– Low drain rate, high energy– Watch & hearing aid applications– Renata, Energizer, Sony

• Secondary battery– 1.6V nominal– High drain rate, high energy– Military & aerospace applications– Yardney, BST, Eagle-Picher

Ag2O + Zn Ag + ZnO

AgO + Zn Ag 2O + ZnO

Ag2O + Zn Ag + ZnO

The better battery.July 12, 2007

Discharge Step 1: Zn + 2AgO → Ag2O + ZnO (1.86V OCV)

Discharge Step 2: Zn + Ag 2O → 2Ag + ZnO (1.59V OCV)

*Size XR41 AgZn cell, 1.5mA discharge rate, room tem p *Size XR41 AgZn cell, room temp charge

Silver-Zinc Discharge & Charge Profile

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Energy Densities Of Primary & Secondary ChemistriesCommercial Button Cell Sizes PR44/SR44/LR44/XR44Energy Densities Of Primary & Secondary ChemistriesCommercial Button Cell Sizes PR44/SR44/LR44/XR44

5CONFIDENTIAL

Zinc Air1600Wh/l

500Wh/kg

Rechargeable

The better battery.July 12, 2007 CONFIDENTIAL

Advancing Silver-Zinc in Three Key AreasAdvancing Silver-Zinc in Three Key Areas

The better battery.

Button Cell Construction

July 12, 2007

• Reliable design with long history• Top and bottom cup

– Material selection for strength & corrosion

– Crimping process is critical

• Gasket design is critical– Material selection– Radial & axial compression– Electrical insulation– Rechargeable electrode flexing

• Interface area determines maximum charge rates

* NiMH has low charge efficiency

ZPower AgZn

Lithium Ion NiMH*

25-40mA/cm2 3-5mA/cm2 10-25mA/cm2

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Button Cell Dimensions & Specifications

8CONFIDENTIAL

AgZnXR44

AgZnXR48

AgZnXR41

AgZnXR70

Cell Capacity (mAh) 120 35 28 18

Cell Energy (mWh) 200 60 47 30

Additional sizes are possible for future designs;Sizes that match existing silver-oxide batteries ar e easiest

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Silver-Zinc Cycle Life & Capacity Fade

July 12, 2007

Reserve Capacity

Traditional rechargeable capacity fade

Cycles (100% Depth of Discharge)

Cap

acity

(m

Ah)

*Size XR41 AgZn cell, room temp charge/discharge

The better battery.

Safe, Water-Based Chemistry

• KOH/H2O based electrolyte like other alkaline chemistries

• Chemistry not susceptible to thermal runaway

• Short circuit testing results in minimal cell heating

• Not subject to proposed FAA battery travel restrictions

July 12, 2007 ZPower Presentation Title

*Size XR48 AgZn cell, room temp (20°C) short circuit test per UL2054

The better battery.

Silver-Zinc As A Clean Technology

• Mercury-free design– Upcoming environmental

regulations– Recycling-friendly

• Recycling – Silver and zinc can be reused– Economical due to silver-content– Existing silver recycling

infrastructure– Easier to meet European battery

recycling targets

• Reduces landfill waste– Rechargeable vs. primary– Packaging waste

July 12, 2007

Metals Recycler ZPower

Retailer

The better battery.

Silver-Zinc Self-discharge Rate

• Cells in room temperature storage• Cells charged to full capacity prior to going into storage• First discharge test results

July 12, 2007 ZPower Presentation Title

Days In

Storage

Storage

Date

Last

Charge

Capacity

Discharge

Capacity

Monthly

Self-

Discharge

Rate

Days In

Storage

Storage

Date

Last

Charge

Capacity

Discharge

Capacity

Monthly

Self-

Discharge

Rate

166 days 15-Jan-10 105 days 17-Mar-10

663 27 26.9 0.07% 2258 27 25.5 1.59%

664 27 26.6 0.27% 2259 27 25 2.12%

665 27 24.8 1.47% 2260 27 26.9 0.11%

666 27 25.3 1.14% 2261 27 27.5 -0.53%

Average 27 25.9 0.74% Average 27 26.2 0.82%

Max 27 26.9 1.47% Max 27 27.5 2.12%

Min 27 24.8 0.07% Min 27 25.0 -0.53%

The better battery.

Recovering Over-Discharged Silver-Zinc Batteries

July 12, 2007 ZPower Presentation Title

4 Days1 Day

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Qualification Testing On Silver-Zinc

Safety Environmental Mechanical Electrical Performance

Short circuitHigh temperature

storageMechanicaldurability

Over-dischargerecovery

Pulse discharge

Abnormal charge Humidity + TemperatureOver-discharge

leakageSelf-discharge Operational

temperature

Crush Corrosion Vibration Cycle life

Impact Chemical compatibility Impact Impedance

Drop Thermal cycling

Shock

Vibration

Projectile

Heating

Temperature cycling

Low pressure

UL2054/IEC62133

Qualification tests are tailored to product design and use cases

The better battery.

Applications For Silver-Zinc

• Form -factor sensitive devices– Higher value associated with miniaturization– Battery run time is a differentiating feature– Battery is the largest component

• Rechargeable battery fits usage profile– Device can be conveniently recharged– Storing/replacing batteries is inconvenient– Add capability to a device currently using

primary battery

• Safe performance is critical– Thermal runaway cannot be tolerated

July 12, 2007 ZPower Presentation Title

The better battery.

Silver-Zinc SummarySilver-Zinc Summary

• New rechargeable chemistry alternative– Safe, high energy density chemistry– Excellent choice for form-factor sensitive designs– Charge algorithm postpones capacity fade until end of life

• Assembly capacity for 1 million pcs/year– Samples available now in size XR41 and XR48– ISO9001 quality system in place by mid-2011

• Multiple semiconductor companies working on silver- zinc compatible charging IC’s

CONFIDENTIAL 16